<!DOCTYPE html>
<html>
<head>
<title>Friend Wheel</title>
<meta name="description" content="Show the relationships between people using a friend wheel diagram, implemented using circular layout." />
<!-- Copyright 1998-2016 by Northwoods Software Corporation. -->
<meta charset="UTF-8">
<script src="go.js"></script>
<link href="../assets/css/goSamples.css" rel="stylesheet" type="text/css" />  <!-- you don't need to use this -->
<script src="goSamples.js"></script>  <!-- this is only for the GoJS Samples framework -->
<script id="code">
  function WheelLayout() {
    go.CircularLayout.call(this);
  }
  go.Diagram.inherit(WheelLayout, go.CircularLayout);

  // override makeNetwork to set the diameter of each node and ignore the TextBlock label
  /** @override */
  WheelLayout.prototype.makeNetwork = function(coll) {
    var net = go.CircularLayout.prototype.makeNetwork.call(this, coll);
    net.vertexes.each(function(cv) {
      cv.diameter = 20;  // because our desiredSize for nodes is (20, 20)
    });
    return net;
  }

  // override commitNodes to rotate nodes so the text goes away from the center,
  // and flip text if it would be upside-down
  /** @override */
  WheelLayout.prototype.commitNodes = function() {
    go.CircularLayout.prototype.commitNodes.call(this);
    this.network.vertexes.each(function(v) {
      var node = v.node;
      if (node === null) return;
      // get the angle of the node towards the center, and rotate it accordingly
      var a = v.actualAngle;
      if (a > 90 && a < 270) {  // make sure the text isn't upside down
        var textBlock = node.findObject("TEXTBLOCK");
        textBlock.angle = 180;
      }
      node.angle = a;
    });
  };
  // end WheelLayout class


  var highlightColor = "red";  // color parameterization

  function init() {
    if (window.goSamples) goSamples();  // init for these samples -- you don't need to call this
    var $ = go.GraphObject.make;  // for conciseness in defining templates

    myDiagram =
      $(go.Diagram, "myDiagramDiv", // must be the ID or reference to div
        {
          initialAutoScale: go.Diagram.Uniform,
          padding: 10,
          contentAlignment: go.Spot.Center,
          layout:
            $(WheelLayout,  // set up a custom CircularLayout
              // set some properties appropriate for this sample
              {
                arrangement: go.CircularLayout.ConstantDistance,
                nodeDiameterFormula: go.CircularLayout.Circular,
                spacing: 10,
                aspectRatio: 0.7,
                sorting: go.CircularLayout.Optimized
              }),
          isReadOnly: true,
          click: function(e) {  // background click clears any remaining highlighteds
            e.diagram.startTransaction("clear");
            e.diagram.clearHighlighteds();
            e.diagram.commitTransaction("clear");
          }
        });

    // define the Node template
    myDiagram.nodeTemplate =
      $(go.Node, "Horizontal",
        {
          selectionAdorned: false,
          locationSpot: go.Spot.Center,  // Node.location is the center of the Shape
          locationObjectName: "SHAPE",
          mouseEnter: function(e, node) {
            node.diagram.clearHighlighteds();
            node.linksConnected.each(function(l) { highlightLink(l, true); });
            node.isHighlighted = true;
            var tb = node.findObject("TEXTBLOCK");
            if (tb !== null) tb.stroke = highlightColor;
          },
          mouseLeave: function(e, node) {
            node.diagram.clearHighlighteds();
            var tb = node.findObject("TEXTBLOCK");
            if (tb !== null) tb.stroke = "black";
          }
        },
        new go.Binding("text", "text"),  // for sorting the nodes
        $(go.Shape, "Ellipse",
          {
            name: "SHAPE",
            fill: "lightgray",  // default value, but also data-bound
            stroke: "transparent",  // modified by highlighting
            strokeWidth: 2,
            desiredSize: new go.Size(20, 20),
            portId: ""
          },  // so links will go to the shape, not the whole node
          new go.Binding("fill", "color"),
          new go.Binding("stroke", "isHighlighted",
                         function(h) { return h ? highlightColor : "transparent"; })
                        .ofObject()),
        $(go.TextBlock,
          { name: "TEXTBLOCK" },  // for search
          new go.Binding("text", "text"))
      );

    function highlightLink(link, show) {
      link.isHighlighted = show;
      link.fromNode.isHighlighted = show;
      link.toNode.isHighlighted = show;
    }

    // define the Link template
    myDiagram.linkTemplate =
      $(go.Link,
        {
          routing: go.Link.Normal,
          curve: go.Link.Bezier,
          selectionAdorned: false,
          mouseEnter: function(e, link) { highlightLink(link, true); },
          mouseLeave: function(e, link) { highlightLink(link, false); }
        },
        $(go.Shape,
          new go.Binding("stroke", "isHighlighted",
                         function(h, shape) { return h ? highlightColor : shape.part.data.color; })
                        .ofObject(),
          new go.Binding("strokeWidth", "isHighlighted",
                         function(h) { return h ? 2 : 1; })
                        .ofObject())
      );

    generateGraph();
  }

  function generateGraph() {
    var names = [
      "Joshua", "Daniel", "Robert", "Noah", "Anthony",
      "Elizabeth", "Addison", "Alexis", "Ella", "Samantha",
      "Joseph", "Scott", "James", "Ryan", "Benjamin",
      "Walter", "Gabriel", "Christian", "Nathan", "Simon",
      "Isabella", "Emma", "Olivia", "Sophia", "Ava",
      "Emily", "Madison", "Tina", "Elena", "Mia",
      "Jacob", "Ethan", "Michael", "Alexander", "William",
      "Natalie", "Grace", "Lily", "Alyssa", "Ashley",
      "Sarah", "Taylor", "Hannah", "Brianna", "Hailey",
      "Christopher", "Aiden", "Matthew", "David", "Andrew",
      "Kaylee", "Juliana", "Leah", "Anna", "Allison",
      "John", "Samuel", "Tyler", "Dylan", "Jonathan",
    ];

    var nodeDataArray = [];
    for (var i = 0; i < names.length; i++) {
      nodeDataArray.push({ key: i, text: names[i], color: go.Brush.randomColor(128, 240) });
    }

    var linkDataArray = [];
    var num = nodeDataArray.length;
    for (var i = 0; i < num * 2; i++) {
      var a = Math.floor(Math.random() * num);
      var b = Math.floor(Math.random() * num / 4) + 1;
      linkDataArray.push({ from: a, to: (a + b) % num, color: go.Brush.randomColor(0, 127) });
    }

    myDiagram.model = new go.GraphLinksModel(nodeDataArray, linkDataArray);
  }
</script>
</head>
<body onload="init()">
<div id="sample">
  <h3>GoJS Friend Wheel</h3>
  <div id="myDiagramDiv" style="border: solid 1px black; background: white; width: 100%; height: 600px" ></div>
  <p>
  This "friend wheel" demonstrates the use of <a>CircularLayout</a>.
  The layout has been customized to make sure each node is considered to have a fixed diameter,
  ignoring the size of any <a>TextBlock</a>.
  </p>
  <p>
  The custom layout also rotates each <a>Node</a> according to the actual angle at which the node was positioned.
  This information is available on the <a>CircularVertex</a> used by the <a>LayoutNetwork</a> that
  the <a>CircularLayout</a> constructs from the nodes and links of the diagram.
  Furthermore, when laying out the nodes it also flips the angle of the <a>TextBlock</a> so that the
  text is not upside-down.
  </p>
  <p>
  <a>GraphObject.mouseEnter</a> and <a>GraphObject.mouseLeave</a> event handlers on the <a>Node</a> template
  highlight both the Node and all of the Links that connect with the Node.
  The same event handlers on the <a>Link</a>s highlight that Link and both connected Nodes.
  Changes made in these event handlers automatically are not recorded in the <a>UndoManager</a>,
  although this sample does not enable the UndoManager anyway.
  </p>
</div>
</body>
</html>